Arizona Diamondbacks: What's Wrong with Ian Kennedy?

Ian Kennedy got shelled again on Wednesday. After four consecutive quality starts, the Arizona Diamondbacks' former 21-game winner surrendered eight hits and six runs to the Pittsburgh Pirates in just four innings of work. The performance on Wednesday was particularly jarring because many fans were starting to believe that Kennedy was beginning to return to his brilliant 2011 form.

Now, though, reality may be sinking in: There's something wrong with Ian Kennedy. But what is it?

The main difference between Kennedy's amazing campaign in 2011 and his disappointing season so far has been the number of hits he's surrendered. In 222 innings last year, Kennedy gave up only 186 hits on a BABIP of .270. This year, he's allowed hitters a BABIP of .318. He's surrendered 162 hits in only 145 innings.

In most cases, BABIP (batting average on balls in play) is highly uncontrollable by the pitcher. It basically comes down to luck. In Kennedy's case, there's not a lot in his statistics to indicate anything beyond bad fortune. He's allowing hitters a line drive rate that's nearly identical to what he allowed last year, and he's giving up only 3 percent more fly balls than he did in 2011.

About 11 percent of Kennedy's fly balls are resulting in homers, which is slightly above the league average, but not substantially so. Pitchers have some measurable control over home runs allowed, but luck still plays something of a factor.

Of the things Kennedy can control—namely walks and strikeouts—Kennedy's numbers this year have actually improved. His strikeouts are down just slightly, from 8.03 per nine innings to 7.82. But he's also cut his walks from 2.23 per nine innings to 1.86. That has resulted in a 15 percent improvement in Kennedy's walk-to-strikeout ratio over last year.

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So, there doesn't seem to be anything Kennedy's doing that explains such a drop-off in performance. And that's where things get a little interesting. psychologically. You see, there's nothing really wrong with Kennedy; the numbers show he's just been the victim of some bad luck.

There's actually something wrong with our expectations of him.

Last year, Kennedy was actually quite lucky in accumulating his 21 wins. His .270 BABIP was well below the league average, which usually sits right around .300. He allowed home runs on under 8 percent of fly balls, also below league average. Finally, he stranded nearly 80 percent of runners he allowed to reach base. That's well above the league average figure of 72 percent. Add all that up, and it becomes clear that we unreasonably expected Kennedy's good luck to carry over from last year.

The truth is, Kennedy was very good last year, but was also quite lucky. This year, he's been just about as good, but far less fortunate. Our expectations were too high after his excellent 2011 season.

In a way, Ian Kennedy is a good case study in managing our expectations as fans. There's really nothing wrong with him this season—he's practically the same pitcher. His true talent lies somewhere in between what he's done this year and what he did last year.

So, it turns out, there might not be anything wrong with Ian Kennedy at all.